Toxicity,penetration, and metabolism of AC 217,300 (AMDRO) in the tobacco budworm (Heliothis virescens) by various methods of application

Penetration was found to be the major factor in the selective toxicity of AC 217,300 in Heliothis virescens larvae. When applied topically in either acetone or dimethyl sulfoxide solutions, less than 3 and 11%, respectively, of the applied dose penetrated the cuticle after 72 hr. Ingestion resulted in tissue residues of 45–55% of the applied dose, and increased toxicity 40 to 140-fold over topical application. Five primary metabolites were tentatively identified by cochromatography with authentic standards. At least 10 other minor metabolites were detected. The lack of insecticidal activity with any of the known metabolites, as well as the tissue residues and metabolic profile, suggested that AC 217,300 is the actual toxicant.